JUCE  v5.4.1-191-g0ab5e696f
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juce::NetworkServiceDiscovery::AvailableServiceList Struct Reference

Watches the network for broadcasts from Advertiser objects, and keeps a list of all the currently active instances. More...

#include <juce_NetworkServiceDiscovery.h>

Inheritance diagram for juce::NetworkServiceDiscovery::AvailableServiceList:
Collaboration diagram for juce::NetworkServiceDiscovery::AvailableServiceList:

Public Member Functions

 AvailableServiceList (const String &serviceTypeUID, int broadcastPort)
 Creates an AvailableServiceList that will bind to the given port number and watch the network for Advertisers broadcasting the given service type. More...
 
 ~AvailableServiceList () override
 Destructor. More...
 
std::vector< ServicegetServices () const
 Returns a list of the currently known services. More...
 

Public Attributes

std::function< void()> onChange
 A lambda that can be set to recieve a callback when the list changes. More...
 

Private Types

enum  { realtimeAudioPriority = -1 }
 Special realtime audio thread priority. More...
 
using ThreadID = void *
 A value type used for thread IDs. More...
 

Private Member Functions

void addListener (Listener *)
 Add a listener to this thread which will receive a callback when signalThreadShouldExit was called on this thread. More...
 
void cancelPendingUpdate () noexcept
 This will stop any pending updates from happening. More...
 
ThreadID getThreadId () const noexcept
 Returns the ID of this thread. More...
 
const StringgetThreadName () const noexcept
 Returns the name of the thread. More...
 
void handleAsyncUpdate () override
 Called back to do whatever your class needs to do. More...
 
void handleMessage (const XmlElement &)
 
void handleMessage (const Service &)
 
void handleUpdateNowIfNeeded ()
 If an update has been triggered and is pending, this will invoke it synchronously. More...
 
bool isThreadRunning () const
 Returns true if the thread is currently active. More...
 
bool isUpdatePending () const noexcept
 Returns true if there's an update callback in the pipeline. More...
 
void notify () const
 Wakes up the thread. More...
 
void removeListener (Listener *)
 Removes a listener added with addListener. More...
 
void removeTimedOutServices ()
 
void run () override
 Must be implemented to perform the thread's actual code. More...
 
void setAffinityMask (uint32 affinityMask)
 Sets the affinity mask for the thread. More...
 
bool setPriority (int priority)
 Changes the thread's priority. More...
 
void signalThreadShouldExit ()
 Sets a flag to tell the thread it should stop. More...
 
void startThread ()
 Starts the thread running. More...
 
void startThread (int priority)
 Starts the thread with a given priority. More...
 
bool stopThread (int timeOutMilliseconds)
 Attempts to stop the thread running. More...
 
bool threadShouldExit () const
 Checks whether the thread has been told to stop running. More...
 
void triggerAsyncUpdate ()
 Causes the callback to be triggered at a later time. More...
 
bool wait (int timeOutMilliseconds) const
 Suspends the execution of this thread until either the specified timeout period has elapsed, or another thread calls the notify() method to wake it up. More...
 
bool waitForThreadToExit (int timeOutMilliseconds) const
 Waits for the thread to stop. More...
 

Static Private Member Functions

static bool currentThreadShouldExit ()
 Checks whether the current thread has been told to stop running. More...
 
static ThreadgetCurrentThread ()
 Finds the thread object that is currently running. More...
 
static ThreadID getCurrentThreadId ()
 Returns an id that identifies the caller thread. More...
 
static void initialiseJUCE (void *jniEnv, void *jContext)
 Initialises the JUCE subsystem for projects not created by the Projucer. More...
 
static void launch (std::function< void()> functionToRun)
 Invokes a lambda or function on its own thread. More...
 
static void setCurrentThreadAffinityMask (uint32 affinityMask)
 Changes the affinity mask for the caller thread. More...
 
static void setCurrentThreadName (const String &newThreadName)
 Changes the name of the caller thread. More...
 
static bool setCurrentThreadPriority (int priority)
 Changes the priority of the caller thread. More...
 
static void sleep (int milliseconds)
 Suspends the execution of the current thread until the specified timeout period has elapsed (note that this may not be exact). More...
 
static void yield ()
 Yields the current thread's CPU time-slot and allows a new thread to run. More...
 

Private Attributes

CriticalSection listLock
 
std::vector< Serviceservices
 
String serviceTypeUID
 
DatagramSocket socket { true }
 

Detailed Description

Watches the network for broadcasts from Advertiser objects, and keeps a list of all the currently active instances.

Just create an instance of AvailableServiceList and it will start listening - you can register a callback with its onChange member to find out when services appear/disappear, and you can call getServices() to find out the current list.

See also
Service, Advertiser

Member Typedef Documentation

◆ ThreadID

using juce::Thread::ThreadID = void*
inherited

A value type used for thread IDs.

See also
getCurrentThreadId(), getThreadId()

Member Enumeration Documentation

◆ anonymous enum

anonymous enum
inherited

Special realtime audio thread priority.

This priority will create a high-priority thread which is best suited for realtime audio processing.

Currently, this priority is identical to priority 9, except when building for Android with OpenSL/Oboe support.

In this case, JUCE will ask OpenSL/Oboe to construct a super high priority thread specifically for realtime audio processing.

Note that this priority can only be set before the thread has started. Switching to this priority, or from this priority to a different priority, is not supported under Android and will assert.

For best performance this thread should yield at regular intervals and not call any blocking APIs.

See also
startThread, setPriority, sleep, WaitableEvent
Enumerator
realtimeAudioPriority 

Constructor & Destructor Documentation

◆ AvailableServiceList()

juce::NetworkServiceDiscovery::AvailableServiceList::AvailableServiceList ( const String serviceTypeUID,
int  broadcastPort 
)

Creates an AvailableServiceList that will bind to the given port number and watch the network for Advertisers broadcasting the given service type.

This will only detect broadcasts from an Advertiser object with a matching serviceTypeUID value, and where the broadcastPort matches.

◆ ~AvailableServiceList()

juce::NetworkServiceDiscovery::AvailableServiceList::~AvailableServiceList ( )
override

Destructor.

Member Function Documentation

◆ addListener()

void juce::Thread::addListener ( Listener )
inherited

Add a listener to this thread which will receive a callback when signalThreadShouldExit was called on this thread.

See also
signalThreadShouldExit, removeListener

◆ cancelPendingUpdate()

void juce::AsyncUpdater::cancelPendingUpdate ( )
noexceptinherited

This will stop any pending updates from happening.

If called after triggerAsyncUpdate() and before the handleAsyncUpdate() callback happens, this will cancel the handleAsyncUpdate() callback.

Note that this method simply cancels the next callback - if a callback is already in progress on a different thread, this won't block until the callback finishes, so there's no guarantee that the callback isn't still running when the method returns.

◆ currentThreadShouldExit()

static bool juce::Thread::currentThreadShouldExit ( )
staticinherited

Checks whether the current thread has been told to stop running.

On the message thread, this will always return false, otherwise it will return threadShouldExit() called on the current thread.

See also
threadShouldExit

◆ getCurrentThread()

static Thread* juce::Thread::getCurrentThread ( )
staticinherited

Finds the thread object that is currently running.

Note that the main UI thread (or other non-JUCE threads) don't have a Thread object associated with them, so this will return nullptr.

◆ getCurrentThreadId()

Thread::ThreadID juce::Thread::getCurrentThreadId ( )
staticinherited

Returns an id that identifies the caller thread.

To find the ID of a particular thread object, use getThreadId().

Returns
a unique identifier that identifies the calling thread.
See also
getThreadId

Referenced by juce::ThreadLocalValue< Type >::get(), and juce::ThreadLocalValue< Type >::releaseCurrentThreadStorage().

◆ getServices()

std::vector<Service> juce::NetworkServiceDiscovery::AvailableServiceList::getServices ( ) const

Returns a list of the currently known services.

◆ getThreadId()

ThreadID juce::Thread::getThreadId ( ) const
noexceptinherited

Returns the ID of this thread.

That means the ID of this thread object - not of the thread that's calling the method. This can change when the thread is started and stopped, and will be invalid if the thread's not actually running.

See also
getCurrentThreadId

◆ getThreadName()

const String& juce::Thread::getThreadName ( ) const
inlinenoexceptinherited

Returns the name of the thread.

This is the name that gets set in the constructor.

References JUCE_CALLTYPE.

◆ handleAsyncUpdate()

void juce::NetworkServiceDiscovery::AvailableServiceList::handleAsyncUpdate ( )
overrideprivatevirtual

Called back to do whatever your class needs to do.

This method is called by the message thread at the next convenient time after the triggerAsyncUpdate() method has been called.

Implements juce::AsyncUpdater.

◆ handleMessage() [1/2]

void juce::NetworkServiceDiscovery::AvailableServiceList::handleMessage ( const XmlElement )
private

◆ handleMessage() [2/2]

void juce::NetworkServiceDiscovery::AvailableServiceList::handleMessage ( const Service )
private

◆ handleUpdateNowIfNeeded()

void juce::AsyncUpdater::handleUpdateNowIfNeeded ( )
inherited

If an update has been triggered and is pending, this will invoke it synchronously.

Use this as a kind of "flush" operation - if an update is pending, the handleAsyncUpdate() method will be called immediately; if no update is pending, then nothing will be done.

Because this may invoke the callback, this method must only be called on the main event thread.

◆ initialiseJUCE()

static void juce::Thread::initialiseJUCE ( void *  jniEnv,
void *  jContext 
)
staticinherited

Initialises the JUCE subsystem for projects not created by the Projucer.

On Android, JUCE needs to be initialised once before it is used. The Projucer will automatically generate the necessary java code to do this. However, if you are using JUCE without the Projucer or are creating a library made with JUCE intended for use in non-JUCE apks, then you must call this method manually once on apk startup.

You can call this method from C++ or directly from java by calling the following java method:

com.roli.juce.Java.initialiseJUCE (myContext);

Note that the above java method is only available in Android Studio projects created by the Projucer. If you need to call this from another type of project then you need to add the following java file to your project:

package com.roli.juce;
public class Java
{
static { System.loadLibrary ("juce_jni"); }
public native static void initialiseJUCE (Context context);
}
Parameters
jniEnvthis is a pointer to JNI's JNIEnv variable. Any callback from Java into C++ will have this passed in as it's first parameter.
jContextthis is a jobject referring to your app/service/receiver/ provider's Context. JUCE needs this for many of it's internal functions.

◆ isThreadRunning()

bool juce::Thread::isThreadRunning ( ) const
inherited

Returns true if the thread is currently active.

◆ isUpdatePending()

bool juce::AsyncUpdater::isUpdatePending ( ) const
noexceptinherited

Returns true if there's an update callback in the pipeline.

◆ launch()

static void juce::Thread::launch ( std::function< void()>  functionToRun)
staticinherited

Invokes a lambda or function on its own thread.

This will spin up a Thread object which calls the function and then exits. Bear in mind that starting and stopping a thread can be a fairly heavyweight operation, so you might prefer to use a ThreadPool if you're kicking off a lot of short background tasks.

Also note that using an anonymous thread makes it very difficult to interrupt the function when you need to stop it, e.g. when your app quits. So it's up to you to deal with situations where the function may fail to stop in time.

◆ notify()

void juce::Thread::notify ( ) const
inherited

Wakes up the thread.

If the thread has called the wait() method, this will wake it up.

See also
wait

◆ removeListener()

void juce::Thread::removeListener ( Listener )
inherited

Removes a listener added with addListener.

◆ removeTimedOutServices()

void juce::NetworkServiceDiscovery::AvailableServiceList::removeTimedOutServices ( )
private

◆ run()

void juce::NetworkServiceDiscovery::AvailableServiceList::run ( )
overrideprivatevirtual

Must be implemented to perform the thread's actual code.

Remember that the thread must regularly check the threadShouldExit() method whilst running, and if this returns true it should return from the run() method as soon as possible to avoid being forcibly killed.

See also
threadShouldExit, startThread

Implements juce::Thread.

◆ setAffinityMask()

void juce::Thread::setAffinityMask ( uint32  affinityMask)
inherited

Sets the affinity mask for the thread.

This will only have an effect next time the thread is started - i.e. if the thread is already running when called, it'll have no effect.

See also
setCurrentThreadAffinityMask

◆ setCurrentThreadAffinityMask()

void juce::Thread::setCurrentThreadAffinityMask ( uint32  affinityMask)
staticinherited

Changes the affinity mask for the caller thread.

This will change the affinity mask for the thread that calls this static method.

See also
setAffinityMask

References juce::ignoreUnused(), and jassertfalse.

◆ setCurrentThreadName()

void juce::Thread::setCurrentThreadName ( const String newThreadName)
staticinherited

Changes the name of the caller thread.

Different OSes may place different length or content limits on this name.

References JUCE_AUTORELEASEPOOL, juce::juceStringToNS(), juce::BlocksProtocol::setName, and juce::String::toRawUTF8().

◆ setCurrentThreadPriority()

static bool juce::Thread::setCurrentThreadPriority ( int  priority)
staticinherited

Changes the priority of the caller thread.

Similar to setPriority(), but this static method acts on the caller thread. May return false if for some reason the priority can't be changed.

See also
setPriority

◆ setPriority()

bool juce::Thread::setPriority ( int  priority)
inherited

Changes the thread's priority.

May return false if for some reason the priority can't be changed.

Parameters
prioritythe new priority, in the range 0 (lowest) to 10 (highest). A priority of 5 is normal.
See also
realtimeAudioPriority

◆ signalThreadShouldExit()

void juce::Thread::signalThreadShouldExit ( )
inherited

Sets a flag to tell the thread it should stop.

Calling this means that the threadShouldExit() method will then return true. The thread should be regularly checking this to see whether it should exit.

If your thread makes use of wait(), you might want to call notify() after calling this method, to interrupt any waits that might be in progress, and allow it to reach a point where it can exit.

See also
threadShouldExit, waitForThreadToExit

◆ sleep()

void juce::Thread::sleep ( int  milliseconds)
staticinherited

Suspends the execution of the current thread until the specified timeout period has elapsed (note that this may not be exact).

The timeout period must not be negative and whilst sleeping the thread cannot be woken up so it should only be used for short periods of time and when other methods such as using a WaitableEvent or CriticalSection are not possible.

Referenced by juce::OpenGLContext::NativeContext::initialiseOnRenderThread(), and juce::OpenGLContext::NativeContext::swapBuffers().

◆ startThread() [1/2]

void juce::Thread::startThread ( )
inherited

Starts the thread running.

This will cause the thread's run() method to be called by a new thread. If this thread is already running, startThread() won't do anything.

See also
stopThread

◆ startThread() [2/2]

void juce::Thread::startThread ( int  priority)
inherited

Starts the thread with a given priority.

Launches the thread with a given priority, where 0 = lowest, 10 = highest. If the thread is already running, its priority will be changed.

See also
startThread, setPriority, realtimeAudioPriority

◆ stopThread()

bool juce::Thread::stopThread ( int  timeOutMilliseconds)
inherited

Attempts to stop the thread running.

This method will cause the threadShouldExit() method to return true and call notify() in case the thread is currently waiting.

Hopefully the thread will then respond to this by exiting cleanly, and the stopThread method will wait for a given time-period for this to happen.

If the thread is stuck and fails to respond after the timeout, it gets forcibly killed, which is a very bad thing to happen, as it could still be holding locks, etc. which are needed by other parts of your program.

Parameters
timeOutMillisecondsThe number of milliseconds to wait for the thread to finish before killing it by force. A negative value in here will wait forever.
Returns
true if the thread was cleanly stopped before the timeout, or false if it had to be killed by force.
See also
signalThreadShouldExit, threadShouldExit, waitForThreadToExit, isThreadRunning

◆ threadShouldExit()

bool juce::Thread::threadShouldExit ( ) const
inherited

Checks whether the thread has been told to stop running.

Threads need to check this regularly, and if it returns true, they should return from their run() method at the first possible opportunity.

See also
signalThreadShouldExit, currentThreadShouldExit

◆ triggerAsyncUpdate()

void juce::AsyncUpdater::triggerAsyncUpdate ( )
inherited

Causes the callback to be triggered at a later time.

This method returns immediately, after which a callback to the handleAsyncUpdate() method will be made by the message thread as soon as possible.

If an update callback is already pending but hasn't happened yet, calling this method will have no effect.

It's thread-safe to call this method from any thread, BUT beware of calling it from a real-time (e.g. audio) thread, because it involves posting a message to the system queue, which means it may block (and in general will do on most OSes).

◆ wait()

bool juce::Thread::wait ( int  timeOutMilliseconds) const
inherited

Suspends the execution of this thread until either the specified timeout period has elapsed, or another thread calls the notify() method to wake it up.

A negative timeout value means that the method will wait indefinitely.

Returns
true if the event has been signalled, false if the timeout expires.

◆ waitForThreadToExit()

bool juce::Thread::waitForThreadToExit ( int  timeOutMilliseconds) const
inherited

Waits for the thread to stop.

This will wait until isThreadRunning() is false or until a timeout expires.

Parameters
timeOutMillisecondsthe time to wait, in milliseconds. If this value is less than zero, it will wait forever.
Returns
true if the thread exits, or false if the timeout expires first.

◆ yield()

void juce::Thread::yield ( )
staticinherited

Yields the current thread's CPU time-slot and allows a new thread to run.

If there are no other threads of equal or higher priority currently running then this will return immediately and the current thread will continue to run.

Member Data Documentation

◆ listLock

CriticalSection juce::NetworkServiceDiscovery::AvailableServiceList::listLock
private

◆ onChange

std::function<void()> juce::NetworkServiceDiscovery::AvailableServiceList::onChange

A lambda that can be set to recieve a callback when the list changes.

◆ services

std::vector<Service> juce::NetworkServiceDiscovery::AvailableServiceList::services
private

◆ serviceTypeUID

String juce::NetworkServiceDiscovery::AvailableServiceList::serviceTypeUID
private

◆ socket

DatagramSocket juce::NetworkServiceDiscovery::AvailableServiceList::socket { true }
private

The documentation for this struct was generated from the following file: